Murray Bookchin (1929-2006) was an active voice in ecology, anarchist, and communalist movements for more than fifty years. His groundbreaking essay, "Ecology and Revolutionary Thought" (1964), was one of the first to assert that capitalism's grow-or-die ethos was on a dangerous collision course with the natural world that would include the devastation of the planet by global warming. Bookchin is the author of The Ecology of Freedom, among two dozen other books.